The present invention relates to latches for fastening doors, panels and the like.
There are numerous types of latches known in the art for fastening doors, panels and the like. Many types incorporate an actuator within the latch design in order to provide latch operation. One example of such prior art devices is illustrated in U.S. Pat. No. 4,556,244 (""244 Patent) to Robert H. Bisbing and assigned to Southco, Inc., the assignee of the present application, the entire disclosure of which is hereby incorporated by reference herein. The ""244 Patent discloses a compression latch incorporating an actuator in the form of a handle and a pawl operable through rotation of the handle in order to move the pawl between latched and unlatched positions.
Another type of latch incorporating an actuator within the latch design is termed a slam-action latch. The slam-action principal has been widely used in the prior art and has been embodied in various latch designs, which usually incorporate a housing which encloses several components, one of which is a sliding-bolt element or pawl. The general characteristic of this type of latch is that it is activated to secure a first member, such as a door, by cooperation of a striker or keeper mounted on a second member, such a door frame, when the door is merely pushed shut or slammed, but some operation of the latch mechanism is required to release the latch and open the door. Examples of such types of latches are illustrated in U.S. Pat. Nos. 3,850,464 (""464 Patent) and U.S. Pat. No. 3,841,874 (""874 Patent) each to James H. Vickers and Robert H. Bisbing and assigned to Southco, Inc., the assignee of the present invention, the entire disclosures of which are herein incorporated by reference. The ""464 and ""874 Patents each disclose a spring-loaded bolt element or pawl having a cam surface cooperating with a striker surface on the door frame as the door is moved into a closed position. The spring force thereafter urges the bolt element or pawl to engage behind the door frame or to engage a keeper element provided on the door frame. In order to open the door when latched against the cabinet frame, a hand grip is provided on the housing to operate the mechanism which withdraws the end of the bolt element from engagement with the door frame or the keeper.
Examples of additional types of slam latches are illustrated in U.S. Pat. Nos. 4,978,152 (""152 Patent) and U.S. Pat. No. D312,769 (""769 Patent), each to Robert H. Bisbing and assigned to Southco, Inc., the assignee of the present invention, the entire disclosures of which are hereby incorporated by reference. The ""152 and ""769 Patents each disclose various types of opening actions of an actuator, such as twisting of a knob or a key or pushing a knob or other activation means, to provide retraction of the pawl in order to unfasten the latch and allow the door to be pulled open away from the frame.
There have been certain drawbacks noted in the foregoing types of prior art fasteners. One noted disadvantage in some prior art devices is that the handle projects outwardly from the enclosure to which the latch is mounted, which can cause unwanted operation of the latch through inadvertent contact on the handle by an operator or other structure. Also, in some instances, such types of latches are considered less desirable for aesthetic reasons since the handle is readily visible.
Another drawback noted with prior art slam latches that have a push-button as the latch actuator is that the knob or other push-button is required to be in an extended position in order to close the door. Also, such designs typically employ a mechanical spring to provide the push-to-open and push-to-close action.
Still another drawback observed in some prior art devices is that one or more flats is required to be incorporated into the housing of the latch and which is received into a correspondingly configured mounting hole to prevent unwanted rotation, which requires significant panel preparation.
In addition, another drawback noted in the prior art is that in operation a person can be trapped inside of an enclosure since the latch actuator is positioned on the opposite side of the latch.
Still another disadvantage noted with prior art latches is attributed to the relationship between the bolt element or pawl and keeper. In particular, latching is accomplished as the pawl engages behind the keeper, which requires precise placement of the pawl relative to the keeper or cabinet frame in order to provide proper latch engagement.
Another noted disadvantage with prior art slam latches is that the pawl may not properly latch when the door is not pushed with a sufficient enough force.
Another noted drawback in the prior art is that there is no way to regulate the amount of holding force supplied by the latch.
Still another noted drawback in the prior art is that such latches when secured can become unlatched due to inadvertent contact force or vibration.
Still another drawback noted with prior art devices is that assembly of the separate components can be rather time consuming or cumbersome in order to retain the various elements.
A further drawback noted with prior art latch designs having a separate keeper element is that the latch and keeper portions must be accurately aligned relative to each other to ensure proper operation, which can provide for a more tedious and time consuming process to mount the respective components on closure members.
Still another drawback noted with some prior art latch designs is that one or more stop elements are required to be used in applications utilizing closure members that are positioned flush relative to each other when closed, for example, the one closure member having the latch mounted thereon engages the stop element mounted on another closure member when the closure members are shut. This has the disadvantage that another part must be used, handled and then precisely installed.
The present invention has been developed in view of the foregoing and to overcome the deficiencies of the prior art.
In accordance with the present invention, a keeper is disclosed for use with a latch to secure the latch in a closed position. In addition, the present invention discloses a stop element against which a closure member having a latch and/or the latch itself engages when closed relative to another closure member. As will be described in more detail herein, in one embodiment, a keeper includes means for aligning when mounted on a closure member. In another embodiment, a keeper includes means operating as a stop element against which one of the closure members engage when closed. These keeper and stop features of the present invention can be used with latches of the slam latch type or any of a variety of other different types of latches as well.
It is therefore an object of the present invention to provide a keeper for engagement by a latch in which the keeper includes means for aligning its position when mounted on a closure member.
It is another object of the present invention to provide a keeper incorporating a stop element for engagement by a closure member.
It is still another object of the present invention to provide a latch incorporating an actuator capable of being stowed away in a retracted position so as to assume a low-profile.
It is another object of the present invention to provide a slam-action latch having a push-button type of latch actuator in which latching of the pawl with the keeper can occur either with the push-button in an extended or a retracted position.
It is a further object of the present invention to provide a slam-action latch incorporating a pawl moveable into a partially retracted position when locked and which provides a user-friendly means to actuate the pawl.
Another object of the present invention is to provide a latch incorporating a pawl adapted to engage a keeper in a latched position and in which precise placement of the keeper is not required to provide proper engagement with the pawl and also which accommodates for some misalignment of the pawl with the keeper and/or the respective members to which the latch carrying the pawl and the keeper are attached.
Still a further object of the present invention is to provide a latch capable of being non-rotatably mounted in a member such as a door panel without requiring significant preparation of the mounting hole.
Still a further object of the present invention is to provide a slam-action latch which provides for a quick and simplified assembly.
It is a still further object of the present invention to provide a latch incorporating an actuator moveable between extended and retracted positions in which the parts are few and which are sufficiently durable in operation.
These and other features, objects and advantages of the present invention will become more readily apparent when taken into consideration with the following description and attached drawings.